PhilP,
All I have is inkjet but I can probably find someone who’ll let me use a laser printer. By all means, please share your idea.
Hotbox
Amongst other things, I have to create 'overlays' for the RC Trains transmitters I build..
For this I use an A4 (European standard letter-size of paper, 210x297mm) self adhesive label stock, which is designed for use on shipping containers. Once stuck, and left for a while, they do not come off!
Obviously they are a 'plastic' rather than paper, can take inkjet or laser-toner, resist sea-water, acid, oil, etc.
You might be able to 'seal' inkjet print with a series of fine coats of (insert spray-varnish / sealer) of choice?
The product I use is:
Buy and view waterproof white plastic labels on A4 sheets here. Choose from 54 sizes including 8 circles in matt white polyethelene. Samples available.
www.labelplanet.co.uk
But once you start looking at this type of thing, you will find a number of different products, all of which will do a similar job.
The above is a UK-based company, but I am sure you will find similar in the US?
(The above will send out a few sample-sheets, certainly to UK addresses, not sure about to the US though?)
Hope this helps?